[TheForge] Heat treating

[Bob Ehrenberger]

Paul,

Most people tend to use the term "tempering" to represent the whole heat 
treating process, and don't understand that tempering is just one part of 
the process.

I had someone try to tell me that if I used a spring to make tools that it 
would return to it's curved shape at a later time. I tried to tell him that 
when I heated it up, it reset it's shape never to return. In the end we had 
to agree to disagree. You have to decide what you want to fight about, once 
there is an impass figure out a way to change the subject. It doesn't do 
your demonstration any good to argue with the customers.

Robert Ehrenberger
Shelbyville, Mo.
eforge at centurytel.net

On Mon, Dec 5, 2011 at 9:59 PM, Paul Novorolsky <crosspein at sbcglobal.net> 
wrote:
> During a public demonstration last weekend, I was explaining to someone
> about hardening and tempering in pretty general terms. When I said that
> tempering sacrifices some hardness for toughness, a spectator told me I
> was wrong. He pretty much said "No it doesn't, tempering makes it harder".
>
> I disagreed assuming he had hardness and toughness confused, stating
> that the heat treating charts for common steels show a reduction in
> hardness at various tempering levels. He continued to tell me I was
> wrong, because he had bought 100's of tons of "full hard stainless
> steel" and asked how I explain that material. I told him I had no
> knowledge of it, but tool steels will lose some hardness during
> tempering. He repeated that I was wrong. At that point I was agitated,
> and told him to do some research and he'll see that tempering does
> result in loss of hardness, at which time his wife seemed annoyed with
> him and dragged him out of our shop. (amusing in itself, as he was a big
> man)